Press for forging or shaping metal



Aug. I2, 1930. J. E. DOBSON 1,772,599

PRESS FOR FORGING OR SHAPING METAL Filed Dec. 27, 1926 v 4 Sheets-Sheet 1' E Af I I 0 i 2 gnoewio'z Aug. 12, 1930. J. E. DOBSON PRESS FOR FORGING 0R SHAPING METAL Filed D60. 27, 1926 4 Sheets-Sheet 2 Aug. 12, 1930. J DOBSQN 1,772,599

PRESS FOR IFORGING on SHAPING IETAL Filed Doc- 27, 1926 4 SheetsSheet 3 (1430: neg, S

Aug. 12, 1930. J DQBSQN 1,772,599

P RESS FORFORGING 0R SHAPING IETAL Filed Dec. 27. 1926 4 Sheets-Sheet 4 Pea g a: my

of presses and machines. Itis the general purposeand object of the invention to provide a press ofthischaracter Patented Aug.- 12,

- UNITED PATENTOFFICE;

JOHN E. DOBSON,0F-'CLEVELAN1), 01110, ASSIGNOR TO THE o nvELANn Pomona;

SHEAR WORKS COMPANY, OF CLEVELAND, 01110, A CORPORATION OF OHIO rnnssiron rename on SHAPING METAL Application filed December 27, 1926. Serial No. 157,107.

This invention relatesto, pressesfor forg ing or shaping metal, ancl more particularly to presses of the type wherein the metal to be forged or shaped is held between clampthe invention shown and'described herein is particularly applicableto presses for forging metal, it Willbe, evidentthat itis.

capable of use in connection with other types witlrmeans whereby the metal to be forged or shaped is held firmlyclampedprior to the 1 actual engagement of the forging orshaping die therewith and is retained in such clamped position until after the said dieishallhavc, completed its forging or shaping operation.

A further object of the invention is "to sea cure a sufiicient "dwell of :the work-clamping member against the work to. clamp the latter w during the entire period that the forging or shaping dieis in engagement therewith and without recourse to cams orcam shafts which have proven unsat sfactory for this purpose,

' especially in heavy forge-pressoperations.

A still further object of the invention is to enable the shaft; byfWhlCll the forging or 1 shaping die is reciprocated to/operate a work-clamping Imernber in; {such manner as to produce a dwell in such memberwhile in work-engaging position meanwhile operating such member by means of al connection 1 which moves continuously with the shaft.

I accomplish theforegoing object and other and morelimited objects whichwill be set forth hereinafter,in and through'the con struction and arrangement of partsshown in, the drawings hereof,- wherein; Fig.1 repre sents. a rfront elevation of a press embodying my invention and showingtlie parts in the positions which they occupyywhen the forging or shaping die is at the bottom of its stroke; Fig. 2-is a view, similar to Fig. 1', showing. the positions of the parts when the forging or shapinglydie is at:0r near the top of its stroke; Fig. 3 is a side elevation of theTsaid machine, with, the parts as shown in Fig; j 1 ,fi-Figs... 1,2 5: i and 61 iare ,=diagrammati viewsjshowing the relativevpositions of the partsfor operating the movableclamping;

die from the drive shaft, in different angu lar positions of saidshaftrand Fig.7 is a,

diagram illustrating the relative movements characters, 1 represents the bed of a press of theeforgmg or punch ng type and zthe supporting base for, said bed. From onefside of thebase there projects ashelf 3, said shelf being provided with, a guide channel, 4 in v theyupper surfacethereof .for. thereceptionofg 6;, toggle,links, to be described hereinafter.

.Supported byjthe base 2 areiuprights5.; (idenotes a shaft which is mounted illjOllIjnals, provided in @the tops of (the ,uprights. 5 d and in the bottom'of acap 7 securedto saidi'w, uprights by. bolts 8.= The, shaft projects be--.

yond the uprights and .hasone of its ends supported in a bracket-9 extending outwardly and upwardly from one ofsaid uprights. i Drivingmeans, as -a,,pulley ,10,v is :applied to 1 7-; a the shafnbetweenthe bracket 9 and jacent upright .5.

7 About midway between. the uprights 5,- the i shaft is .providedw-ith-an eccentric 11, on which is mounted the collar 12, said-collar 8c.

having a. rod 12- extending downwardly, therefrom and carrying atits lower end a crosshead 13 to the bottom of which the forg-- ing die 14 is secured. The cross head J13 travels between guides 15.on the uprights 5. 85, The end of the shaft 6 which is opposite the bracket 9 extends beyond the upright at such side of the press and is provided with a I crank 16, the pin 16 whereof has a block "17 journaled thereon, the said block being pro vided with trunnion pins 18 to which the upper end of a link 19 is journaled by means of forks 19.

The hell-crank-lever is pivotedat theangle r the, ad-.

The bottom of the link 19 is v forked, as shown at19", and these forks are I connected by trunnion pins 20 with a block '95- between its arms 21 and 22 to a lug 23 on the adjacent upright by means of a stud 24 extending through the said lug and through a hub 25 on said lever. The lower end of the 5 lever arm 22 is forked, as shown at 22, and is connected by a pin 26 with the upper end of a link 27, the lower end whereof is'connected to the joint 28 between a pair of togglelinks 29 and 30. The link 29 is hinged at 31 to a 10 block 32 anchored within the channel 4 by a flange 32' overhanging the shelf and secured thereto by a screw bolt 32". The end of the link which is opposite the pivot 28 is hinged at 33 to a'die carrier 34 to which the 5' movable clamping die 35 is secured, the said die carrier and die being movable along the. top of the bed 1, the channel 4 constituting a continuation of such bed top. Opposed to the movable die carrier 34 and die 35 are the an die carrier 36 and the fixed die 37.

As will appear from the first three figures of the drawings,when the forging die 14 is in its lowermost position (as shown in Fig. 1) the links 29 and 30 will. be straight, with the :6 die 35 in its innermost positionwh ere it is in closest promixity to the fixed die 37. When the die 14 is in its uppermost position (as shownin Fig. 2), the parts 19. 21, 22 and 27 will have been moved upwardly by the shaft in 6 so that the joint 28 will have been elevated,

withdrawing the movable die 35 from its clamping relation with respect to the fixed die 37. In order, however, to obtain a sufficient dwell in the clamping position of the die 35 to enable the work or object subjected to the foregoing operation to be held firmly, not only at the time of impact of the die 14 against such work or material. but prior thereto and until said dieshall have completed its forging or shaping stroke, special connections between the shaft 6 and the die 35 are necessary; i also a special relation must exist between the positions of the eccentric 11 and the crank 16 with relation to the shaft 6. The special connections are those afforded by the parts 19, 21, 22 and 27, and the toggle links 29 and 30, and the mannerin which the e connections operateto secure the foregoing result will be explained in connection with the diagrammatic views in Fi gs. 4-7, inclusive. It should be noted that the parts 16, 19, 22, 27, 29 and 30 areso constructed as to constitute three pairs of toggles, parts 16 and 19 form- 1 ing the first pair, parts 22 and 27 the second pair,'and parts 29 and 30 the third pair, and thatthese toggles are so arranged that the first toggle 1619 is connected to the shaft 6, the third toggle 29--30 is connected to the clamping die 35 and the second toggle 2227 connects the first and third toggles. This arrangement of the three pairs of toggles, andthe setting or timing of the crank 16 and the linksforming the toggles is such 65 as m produce a prolonged dwell of the "clamping die 35 in clamped position and in timed relation to the forging die 14.

Referring first to Figs. 4, 5 and 6, the circle C represents the path of the crank pin 16" and of the extreme projection or high spot of the eccentric 11 during one revolution of the shaft 6, it being assumed, for convenience of illustration, that the said crank pin and such projection of the eccentric are equidistant from the center of rotation of the shaft 6. In Fig. 4, the parts are shown in full lines in the positions which they occupy in Fig. 2, and the direction of rotation of the shaft 6 is that indicated by the arrow. As will appear from this view and the two succeeding views, the crank pin 16 is about 45 in advance of the high spot or extreme projection of the eccentric 11. In this view, it will be observed that, while the crank pin 16"is on its upper center, the link 19 is off center; that is to say, it extends at an angle with respect to a line D connecting the center of the shaft 6 and the joint 28 between the toggle links 29 and 30; also, the link 27.

which is connected with the lower arm 22 of the bell-crank lever, extends at an angle from the toggle joint 28 and in the general direction of the link 30. y

In Fig. 5, the parts are shown in the positions which they will occupy when shaft 6 shall have turned about 135 from the position shown in Fig. 4, which will have resulted in pushing downwardly hpon the link 19 and in rocking inwardly the lev so that said arm and the link 27 are nearly in a straight line coinciding with part of the line D. In this position, it will be seen that the toggle links 29 and 30 are almost straight; and, as will appear by reference to the positions of the parts marked 11 and 16", the die 14 will have completed only about one-half of its downward stroke. I

In Fig.6, the parts areindicated in th positions which they will occupy when the crank pin shall have reached its lower center with the die 14 approaching its bottom center. At this time, the link 19 will have been moved downwardly from the position shown in Fig. 5, throwing the lever arm 22 to the right of the line D; but the links 29 and 30 will be in substantially the same position as shown in Fig. 5; that is to say, the will be substantially straight and will obviously be holding thefmovable die 35 in substantially its innermost position, so that the object or materialclamped between it and the fixed die will be held firmly.

In Fig.4 there are shown in dotted lines the positions which the parts occupy when the die 14 is at the bottomof its stroke. In

this position the high spot or extreme pro tion, and the connections between the crank pin and the toggle links '29 and 30 have resulted in bringing" thefl'ever arm 22 and the link 27 in a straight line,with the result that time when the forging die 14.18 at the bottom of its stroke and exercising its final forging or shaping action upon thQIIIiLtBI'lfLl or work.

It will be seen, from vtheidiagra nmatic' views in Figs. 46 inclusive, that'the links '29 and 30 are held in substantially straightened position, not only during OfthereVOlu- 'tion of the shaft 6, but fora considerable pe- I p v p I proven un'saitisfactory 'when used to perform riod thereafter, as the said links are actually straight at the end of the 90-period shown in said views. As a mat teroffact, the links areheld in such substantially-straightened position during about 120 ofthe rotation of the shaft 6. r i I In Fig. 7 I have shown, by the'upper curved line FD and the lower curved line (1-1), the relative positions of the forging die and of the movable clamping die, respectively, throughout a complete revolution of the shaft 6. In thisview, the degrees through which the shaft 6 rotates while making a complete revolution are indicated by horizontal spaces of 10 each. The extent of the vertical movements of the forging die during such revolution is indicated by the vertical lines extending upwardly from the 'line FD. The positions of the movable diemeanwhile are indicated by the. lower line GD, and the extentof its movements -to-' ward and away from the fixed die bythe vertical lines extending downwardly from the line CD. In practice, the crank pin'16 is 45 in advance of the high spot of the eccentric 11. This brings the highest point of the line CD 45 in advance of the highest point on the line FD, as shown at the right of Fig. 7. By comparisoniof the lines FD and CD with each other, it will be seen that the die 35 is moved to approximately its innermost clamping position whenthe highspot? of the eccentric shall have been moved approximately 90 downwardly and at the time when the crank pin 16 shall have moved approximately 135 downwardly, and that the die is held in such position until after the high point of the eccentric shall have passed its lower center (180). a

By arranging the link 19 atan angle to the line D, as shown, and by employing in effect two toggle connections between the lever arm 21 and the movable die (one at 22, 27 and the other at 29, 30) operating at right angles to ment is negligible as affecting detrimentally "expensive.

theiclampin'g of the work or metal which is operated upon :by the die 14. This arrange ment also enables the dies 35 and 37 to exer cise a powerful gripping action upon the work throughout the entire period ofthe, dwell of the die 35. 5

Byvirtue of the construction and arrange- V ment of the parts shown herein, it is possible tooperate the forging die and the movable :cl'ampingdie from a common shaft and to perform heavy forging operations throughout a long period of time without injurylto the mechanism. Furthermore, it is possible to secure these results by means of an attachment to an existing type of press and without the employment of cams, which-f have 1 work of this character; and the cost of such equipment and installation is relatively in- F or convenience of description, the forging die is assumed as being movable downwardly toward the clamping dies 35.and 37 so that it will h'avereached thebottom of its stroke Hwhen it is'ncarest said clamping dies, and

corresponding descriptive terms are employed therein. However, it is not intended, by this language, 15011111111 my invention to usefin connection with" only a vertically movable cross head and forging die and a horizontally movable clamping die, as it will be evident thatfsofar-asthe movement of the diesand theimode of accomplishing the same iscon-f c'erned, thesame result could be accomplished witlrthe; forging die movable in other thana:

vertical direction and with the movable clampingdie movable in otherthan a hori 'zontal direction. I Y 1 Having thusdescribed my invention, what I'claimis: l

1. In a'machine of the type described, the

combination of a shaft, a orging' or shap .ing die, "connections between said shaft and saiddie for reciprocating thelatter by the rotation of the said shaft, a movable clamping member, and connections betweenlthe ,saidshaft and the said member for movingk the latter intoengagement with the work,

the said connections comprising a toggle, one of the links of which is connected to the mov-f able member, atoggle operating at substantially right angles to the first-mentioned toggle and comprising a link connected to'the joint of'said first toggle, and connections be- 7 tween the last-mentioned link and'said shaft,

including a crank arm carried by the shaft, and a bell crank lever between said crank arm and toggle, the said second toggle prolong- .ing the dwell produced by said first toggle.

2. I [n amachine of the type described, the: combination of a shaft, a forging or shaping die, connections between said shaft and said forging or shaping dle forreciprocatingsaid diei'by the rotation ofsaid shaft, a movable clamping, member, and connections between the said shaft and the said member for moving the latter toward and from the work, the said connections comprising a pair of toggle links, one of which is connected to the said member, a crank carried by said shaft, the said crank having a crank pin, a block journaled on said crank pin, a link having a swiveled connection with said block, a bell-crank lover, a universal connection between one of the arms of said lever and the opposite end of said link a link connected at one end with the joint'of said toggle, and a pivotal connection between the opposite end of said link and the other arm of said lever.

3. In a machine of the type described, the combination of a shaft, a forging or shaping die, connections between said shaft and said die forreciprocating the latter by the rotation of'said shaft, a movable clamping memher and connections between the said shaft and the said member for moving the latter into engagement with the work, the said connections comprising a toggle, one of the links of which is connected to the movable member, a second toggle comprising a link connected to the joint of the first mentioned toggle, and means operated by the rotation of said shaft for operating said link, said second toggle prolonging the dwell produced by said first mentioned toggle. 4. In a machine of the type described, the

combination of a shaft, a forging or shaping die, connections between the said shaft and said die for reciprocating the latter by the rotation of the said shaft, a movable clampin said shaft and the said member for moving the latter into engagement with the work,

the said connections comprising a toggle, one

of the links of which is connected to the movable member, a second toggle operating at main crank, the said main crank being coupled to the heading die for operating the same, and a three-fold toggle lever mechanism connecting the auxiliary crank and the clamping die and coactin with said auxiliary crank on each cycle 0 action of the machine to start the closing of the clamping die before the heading die has started its heading stroke, the three-fold toggle lever mechanism giving a prolonged dwell to the clamping die.

In testimony whereof, I hereunto aflix my signature.

JOHN E. DOBSON.

member, and connections between thev substantially right angles to the first mentioned toggle and comprising a link connected to the joint of said first toggle and connections between the last mentioned link and said shaft, the said second toggle prolonging the dwell produced by the said first toggle. 5. In a machine of the type described, the combination of a shaft, a forging or shaping die, connections between said shaft and sai die for reciprocating the latter by the rot-ation of the said shaft, a movable clamping member and connections between the said shaft and the said member for moving the latter into engagement with the work, the saidconnections comprising a toggle, one of the links of which is connected to the movable member, a second toggle com rising a link connected to the joint of the rst mentioned toggle and means connecting the-said second to gle with the shaft whereby the toggle links of the two toggles will be substantiall straightened and the movable member hel in clamping relation with respect .to'the work before the said die shall have 

